scholarly journals INFLUENCE OF THE NATURE OF THE MODIFIER ON THE SORPTION PROPERTIES OF SHANKANAI ZEOLITE

2021 ◽  
Vol 3 ◽  
pp. 36-46
Author(s):  
R.А. Kaiynbayeva ◽  
◽  
N.N. Kojabekova ◽  
G.Sh. Sultanbayeva ◽  
А.А. Аgatayeva ◽  
...  
Keyword(s):  
Hydrochloric Acid ◽  
Cation Exchange ◽  
Natural Zeolite ◽  
Physicochemical Analysis ◽  
Sorption Properties ◽  
Zeolite A ◽  
Optimal Temperature ◽  
Modified Zeolite ◽  
Modified Zeolites ◽  
Sorption Characteristics

Sorbents modified with hydrochloric acid and chitosan based on the Shankanai bridge formation zeolite were obtained, and the effect of drying temperature on the sorption properties of sorbents was studied. It was found that 25 °C is the optimal temperature for obtaining acid-modified zeolite. A chitosan-modified sorbent with good sorption characteristics can be obtained at 25 °C with cation-exchange (COE 68.05 mg-eq/g) and 70°C with anion-exchange (SEC 70.16 mg-eq/g) properties. Physicochemical analysis of modified zeolites showed an increase in the size of voids and channels on the surface of acid-modified zeolite, and when modified with chitosan, the latter is crosslinked with the surface of natural zeolite.

scholarly journals Fluoride ion adsorption from wastewater using magnesium(II), aluminum(III) and titanium(IV) modified natural zeolite: kinetics, thermodynamics, and mechanistic aspects of adsorption

2017 ◽  
Vol 8 (4) ◽  
pp. 479-489 ◽  
Author(s):  
Zhijun Ma ◽  
Qi Zhang ◽  
Xingyuan Weng ◽  
Changye Mang ◽  
Liwei Si ◽  
...  
Keyword(s):  
Natural Zeolite ◽  
Adsorption Process ◽  
Fluoride Ion ◽  
Ion Adsorption ◽  
Order Model ◽  
Fluoride Ions ◽  
Modified Zeolite ◽  
Fluoride Adsorption ◽  
Pseudo Second Order ◽  
Modified Zeolites

Abstract Natural zeolite was modified using metal ions, including magnesium(II), aluminum(III) and titanium(IV). The modified zeolite was then used as an adsorbent for the investigation of the adsorption kinetics, isotherms, and thermodynamic parameters of fluoride ions in wastewater at various pHs and temperatures. The kinetics and thermodynamics for the removal of the fluoride ions onto the modified zeolite have also been investigated. The fluoride ion adsorption capacity of the three types of modified zeolites exhibited an increase, then decrease, with rising pH. The fluoride adsorption capacity of the modified zeolites decreased with an increase in temperature. The pseudo-second-order model is more suitable for describing the adsorption kinetic data than the pseudo-first-order model for modified zeolite and the adsorption process of the fluoride ions reveals pseudo-second-order kinetic behavior, respectively. It was found that the adsorption equilibrium data fit the Freundlich isothermal equation better than that of the Langmuir isothermal and Dubinin–Radushkevich (D–R) isothermal equations. Thermodynamic analysis suggests that the negative values of ΔG0 and ΔH0 further indicate that the fluoride adsorption process is both spontaneous and exothermic. The results of competitive adsorption tests suggest that the modified metal zeolite materials adsorb fluoride ions with high selectivity.

Effect of natural and modified zeolite addition on anaerobic digestion of piggery waste

2003 ◽  
Vol 48 (6) ◽  
pp. 263-269 ◽  
Author(s):  
Z. Milán ◽  
P. Villa ◽  
E. Sánchez ◽  
S. Montalvo ◽  
R. Borja ◽  
...  
Keyword(s):  
Natural Zeolite ◽  
Organic Load ◽  
Second Phase ◽  
Modified Zeolite ◽  
Waste Solid ◽  
Modified Zeolites ◽  
Two Phases ◽  
Gas Volume ◽  
Potential Biodegradability

The effect of natural and modified zeolites on the anaerobic degradation of acetate and methanol was evaluated by the determination of specific methane productivity (SMP) in batch minidigesters of 50 mL at doses of 0.01, 0.05 and 0.1 g of zeolite/g of VSS. The effects of the different zeolite concentrations were determined by the results of the SMP. A kinetic characterization with data of accumulated methane gas volume was also carried out. In the second phase of the study, the effects of natural and nickel zeolite concentrations were tested with piggery waste in laboratory scale digesters of 2.5 L operating at semi continuous mode, by increasing the organic load applied from 0.2 to 22.0 g TCOD/d corresponding to organic loading rates (OLR) of 0.1-8.8 g TCOD/l.d. A greater effect of modified zeolite on SMP was observed, with an increase of 8.5 times with magnesium zeolite, 4.4 times with cobalt zeolite and 2.8 times with nickel zeolite. Two phases were defined in the kinetic study and an increase of more than 2 times the apparent constant of digesters with modified zeolites was observed in the second phase when compared to unmodified natural zeolite. Modified natural zeolite addition to digesters can allow an increase in the potential biodegradability of piggery waste solid fraction and/or a considerable reduction of digestion volume.

scholarly journals Preparation and application of modified zeolites as adsorbents in wastewater treatment

2018 ◽  
Vol 2017 (3) ◽  
pp. 621-635 ◽  
Author(s):  
Jiahui Shi ◽  
Zixuan Yang ◽  
Hongliang Dai ◽  
Xiwu Lu ◽  
Lihong Peng ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Wastewater Treatment ◽  
Constructed Wetlands ◽  
Natural Zeolite ◽  
Review Paper ◽  
Large Specific Surface Area ◽  
Modified Zeolite ◽  
Modified Zeolites ◽  
Surface Modified ◽  
Modification Treatment

Abstract Natural zeolite has been recognized as a useful adsorbent for wastewater treatment for removing cations. Natural zeolite is a kind of porous material with large specific surface area but limited adsorption capacity. In recent years, emphasis has been given to prepare the surface modified zeolite using various procedures to enhance the potential of zeolite for pollutants. Modification treatment for zeolite can greatly change surface chemistry and pore structure. The article describes various modification methods of zeolite, and introduces the removal mechanisms of common pollutants such as ammonium, phosphorus and heavy metals. In addition, this review paper intends to present feasibility of applying modified zeolite to constructed wetlands which will be beneficial to achieve higher removal effect.

Investigations of the corrosion activity of the KAlCl4 melts by the methods of physicochemical analysis

2019 ◽  
Vol 24 (4) ◽  
pp. 59-66
Author(s):  
E.S. Filatov
Keyword(s):  
Water Vapor ◽  
Hydrochloric Acid ◽  
Input Data ◽  
Corrosion Potential ◽  
Physicochemical Analysis ◽  
Metal Alloys ◽  
Corrosion Activity ◽  
Protection Efficiency ◽  
Gas Atmosphere ◽  
Metal Aluminum

Corrosion behavior of metal alloys in a melt of potassium chloroaluminate (KAlCl4) was investigated. Metal aluminum was used as a protector for protection against continuous frontal corrosion. The equilibrium potentials of aluminum and the corrosion potential of the alloys were measured. The data were obtained to evaluate the corrosion ability of the system of molten salt of potassium chloroaluminate - gas (argon) by measuring the redox potential of the specified environment depending on the composition of the gas atmosphere above it, i.e. from impurities of water vapor, hydrochloric acid, oxygen and other, for example, carbonaceous gases. The calculations of the protection efficiency using the potential difference between the metal aluminum and the protected material were performed. The regularities of changes in the equilibrium potentials of aluminum from the temperature and concentration were established as the fundamental data for possible use at determining the composition ratio of potassium chlorides and aluminum in potassium chloroaluminate as input data for the development of a sensor of composition of chloroaluminate potassium.

ION Exchange Characterisation of Modified Zeolite

1992 ◽  
Vol 26 (9-11) ◽  
pp. 2269-2272 ◽  
Author(s):  
Š Cerjan-Stefanovic ◽  
M. Kaštelan-Macan ◽  
T. Filipan
Keyword(s):  
Drinking Water ◽  
Ion Exchange ◽  
Anion Exchange ◽  
Natural Zeolite ◽  
Deionized Water ◽  
Isomorphous Substitution ◽  
Waste Waters ◽  
Modified Zeolite ◽  
Water Drinking

Isomorphous substitution of phosphorus into a natural zeolite affords the possibility to change the overall framework charge from negative to positive. The substances so created should be used for purification of waste waters. The work describes the preparation of phosphated zeolite, their characterisation and examples of their anion exchange of NO3 on observed in deionized water, drinking water and in the solution containing varying amounts of nitrate.

scholarly journals First Report on the Geologic Occurrence of Natural Na–A Zeolite and Associated Minerals in Cretaceous Mudstones of the Paja Formation of Vélez (Santander), Colombia

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 218
Author(s):  
Carlos Alberto Ríos-Reyes ◽  
German Alfonso Reyes-Mendoza ◽  
José Antonio Henao-Martínez ◽  
Craig Williams ◽  
Alan Dyer
Keyword(s):  
Natural Zeolite ◽  
Scanning Electron Micrographs ◽  
Total Sulfur ◽  
Zeolite A ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mineral Phases ◽  
The World ◽  
Porosity And Permeability ◽  
First Time

This study reports for the first time the geologic occurrence of natural zeolite A and associated minerals in mudstones from the Cretaceous Paja Formation in the urban area of the municipality of Vélez (Santander), Colombia. These rocks are mainly composed of quartz, muscovite, pyrophyllite, kaolinite and chlorite group minerals, framboidal and cubic pyrite, as well as marcasite, with minor feldspar, sulphates, and phosphates. Total organic carbon (TOC), total sulfur (TS), and millimeter fragments of algae are high, whereas few centimeters and not biodiverse small ammonite fossils, and other allochemical components are subordinated. Na–A zeolite and associated mineral phases as sodalite occur just beside the interparticle micropores (honeycomb from framboidal, cube molds, and amorphous cavities). It is facilitated by petrophysical properties alterations, due to processes of high diagenesis, temperatures up to 80–100 °C, with weathering contributions, which increase the porosity and permeability, as well as the transmissivity (fluid flow), allowing the geochemistry remobilization and/or recrystallization of pre-existing silica, muscovite, kaolinite minerals group, salts, carbonates, oxides and peroxides. X-ray diffraction analyses reveal the mineral composition of the mudstones and scanning electron micrographs show the typical cubic morphology of Na–A zeolite of approximately 0.45 mμ in particle size. Our data show that the sequence of the transformation of phases is: Poorly crystalline aluminosilicate → sodalite → Na–A zeolite. A literature review shows that this is an unusual example of the occurrence of natural zeolites in sedimentary marine rocks recognized around the world.

scholarly journals Synthesis of Zeolite-A and Zeolite-Y Using Silica Gel Waste as Silica Source and Modifying with Fe

2018 ◽  
Vol 7 (4.38) ◽  
pp. 1376
Author(s):  
Pornnipa Khaosomboon ◽  
Kulyakorn Khuanmar ◽  
Panomchai Weerayutsil
Keyword(s):  
Surface Area ◽  
Silica Gel ◽  
Zeolite Y ◽  
Physical Adsorption ◽  
Lower Surface ◽  
Zeolite A ◽  
Silica Source ◽  
Bet Specific Surface Area ◽  
Silica Gel Waste ◽  
Modified Zeolites

The purpose of this research was to synthesize zeolite-A (Ze-A) and zeolite-Y (Ze-Y) using silica sources from silica gel waste, and also improving adsorption capacity with Fe which was trapped in the synthesized zeolites:  Ze-Fe-A and Ze-Fe-Y. All synthesized zeolites were tested with lead solution of 40 mg/L at pH 5. For BET specific surface area, the parent Ze-A and Ze-Y presented surface area of 27.02 and 211.42 m2/g, respectively, whereas Ze-Fe-A and Ze-Fe-Y presented a lower surface area of 10.90 and 28.22 m2/g, respectively. SEM and TEM image demonstrated the cubic and polygon shapes for Ze-A and Ze-Y, respectively, while their modification with Fe presented more round shape. Additionally, both modified zeolites with Fe presented higher adsorption efficiency than their parents. Although the modified zeolites gave lower surface area, the efficiency removal of lead showed higher capacity than zeolite without Fe. It could be concluded that the adsorption mechanism of modified zeolites did not only rely on physical adsorption, but also on chemical adsorption.      

Adsorptive removal of trace oxytetracycline from water by acid-modified zeolite: influencing factors

2013 ◽  
Vol 68 (11) ◽  
pp. 2473-2478 ◽  
Author(s):  
Wenhao An ◽  
Hua Xiao ◽  
Man Yu ◽  
Xiaoyang Chen ◽  
Yuxin Xu ◽  
...  
Keyword(s):  
Humic Acid ◽  
Removal Efficiency ◽  
Natural Zeolite ◽  
Opposite Effect ◽  
Swine Wastewater ◽  
Adsorption Efficiency ◽  
Tetracycline Antibiotics ◽  
Modified Zeolite ◽  
Alkaline Conditions ◽  
Acidic Conditions

Because of the wide use of antibiotics in the livestock industry, trace tetracycline antibiotics are frequently detected in swine wastewater and water bodies near pig farms. Based on natural zeolite, modified zeolite was synthesized by treatment with nitric acid. As one kind of typical tetracyclines, oxytetracycline (OTC) was chosen as the target adsorbate. Removal of trace OTC by modified zeolite and the effects of several main water matrices on OTC adsorption were studied in detail. OTC removal efficiency by acid-modified zeolite was about 90%, compared to less than 20% by natural zeolite. In general, in acidic conditions the removal efficiency of OTC by modified zeolite was about 90%, which was much higher than 20–35% in alkaline conditions. An increase in ionic strength from 0.01 to 1.0 M led to a decrease in adsorption efficiency from 90 to 27%. The presence of 10.0 mg L−1 dissolved humic acid accelerated sorption of OTC on modified zeolite, while 100.0 mg L−1 humic acid resulted in the opposite effect. An increase in temperature contributed to enhancing the adsorption efficiency.

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